Studies are proposed on the mechanism of oxidative photosynthetic phosphorylation, using a combination of rapid mixing-quenching techniques, measurement of patterns of labelling and release of bound nucleotides, and measurement of isotopic exchanges and net reaction rates. Also included will be cross-linking experiments to ascertain the orientation of the phosphorylation components in the coupling membrane, and chemical probes of probable protein conformational exchanges during catalysis. Other studies will be directed toward use of aurovertin and a new series of dansyl derivatives that are fluorescent and may act as indicators of conformational change. Additional studies are proposed on the partial reactions of ATPase in various inhibited forms, and experiments to ascertain if alteration of catalytic sites indeed occurs during net ATP synthesis. In other related studies, the phenomenon of cooperative catalysis as observed with pyrophosphate and other enzymes will be studied in more detail to hopefully give a satisfactory description of such phenomenon for one or more enzymes, and to assess the possibility of the general applicability of the phenomenon with many enzymes.